2 GEOLOGICAL MEMOIES. 



In Monte Titano itself the following groups of beds may be dis- 

 tinguished, proceeding from below upwards. 



1. Solid coral-conglomerates, consisting of Porites ramosus, more 

 than 340 feet thick, with remains of large Gasteropods, Bryozoa, 

 Echinoderms, and large heavy Pectens, some of which show a remark- 

 able resemblance to species found in the Yienna Basin (Pecten latis- 

 simus, Holgeri, aduncus, &c). A small Nummulite (Y. planulatus) 

 also occurs here. 



2. Sandy beds, consisting of comminuted remains of Bryozoa, 

 Echinida, and Porites ramosus, with numerous Pectens. 



3. Marly beds, with Porites, Pecten, and Terebratula, and with 

 numerous Echinida and Bryozoa. 



These beds are regarded by the author as belonging to the Lower 

 Miocene and Upper Eocene. 



In all about 70 fossils have been detected in these beds ; but a great 

 part of them can only be approximately determined, owing to their 

 defective state of preservation. The species cited are as follows : — 



Eishes. Sphasrodus ductus, Carcharodon megalodon, Oxyrrhina 

 isocetica, 0. Desorii, Lamna contortidens, L. cuspidata, 

 Lamna, sp. 



Gasteropoda. Natica, sp. ?, Rissoina, sp., Conus, sp., Cassis, sp., 

 Fusus episomus. 



Conchifera. Pecten Haueri, P. Michelotti, P. miocenicus, P. 

 deletus, Pecten, sp., Janira, sp., Lima, sp., Spondylus, sp. 



Brachiopoda. Terebratula bisinuata. 



Bryozoa. Membranipora, sp., Lepralia, sp., Retepora vibicata, 

 Eschara unchdata, E. subchariacea, Yincularia, sp., Discopora, 

 sp., Radiopora, sp., Hornera, sp., H. trabeculars, Myriozoon 

 truncatum. 



Echinodermata. Rhabdocidaris, sp., Ciclaris, sp., C. avenionensis, 

 C. calamus, Psammechinus parvus, Clypeaster scutum, Echin- 

 anilms scutellal, E. Sopitianust, E. Wrighti, E. Beggiatoi?, 

 Echinolampas liemispliairicus, E. Laurillardi, E. discus, E. 

 similis, Conoclypus plagiosomus, Ecliinocyamus Studeri, Peri- 

 aster Heberti?, P. scarabceus?, Pericosmus latus, P. aqualis'?, 

 Linthia cruciata ?, Macropneustes MenegJiinii, M. brissoides ?, 

 M. pidvinatus ?, Eupatagus ornatus, Spatangus ocellatus ? 



Corals. Trocliocyatlius elegans, Stylocoenia, sp., Porites ramosus. 



Eoraminifer. Nummtdites planidatus. 



As regards the distribution of these fossils in the different strata, 

 the Gasteropods may be said to reach their maximum in the coral- 

 conglomerates, the Pectens in the sandy beds, and the Echinida and 

 Bryozoa in the marly deposits, in which also the fossils are best pre- 

 served. There seems to be no difference of age between the strata ; 

 and their differences are consequently to be accounted for solely by 

 external conditions. The author comes to the conclusion that the 

 group of deposits of which Monte Titano is composed must have 

 been formed during a period of depression. [W. S. D.] 



